specific for long-chain thioesters of fatty acids from S-acylated residues in proteins, palmitoyl cysteine and palmitoyl-CoA, catalytic triad of PPT2 consists of Ser111, His283, and Asp228, mechanism, both PPT1 and PPT2 have lipid-binding grooves leading away from the active site

resistance to tumor necrosis factor-induced apoptosis in embryonic fibroblasts derived from Ppt1/Cln1-deficient mice but not from mice with a targeted deletion of Cln3 or Cln5 (murine models of ceroid lipofuscinosis)

first case of infantile neuronal ceroid lipofuscinosis in 37 month old Japanese boy diagnosed by enzyme activity deficiency of palmitoyl-protein thioesterase, displaying symptoms of severe deterioration beginning in his 14th month

PPT1-deficient mouse (PPT1-/-) mimics the clinical symptoms and underlying pathology of infantile neuronal ceroid lipofuscinosis: Purkinje cell loss beginning at 3 months, which correlates with changes in rotarod performance, an early stage reactive gliosis and a primary pathology in astrocytes, including changes in S100beta and GLAST expression, a late stage granule cell loss, microglial activation, and demyelination. Neuronal–glial interactions are the core pathology in the PPT1-/- cerebellum

role of PPT1 and, likely, protein depalmitoylation in the regulation of tumor necrosis factor-induced apoptosis. PPT1 is involved in cell death triggered by death receptors but not receptor-independent cytotoxic agents. Expression of PPT1 cDNA in infantile neuronal ceroid lipofuscinosis cells restores the tumor necrosis factor sensitivity

when injected intravenously into PPT1-deficient mice, the clearance of recombinant PPT1 from plasma is rapid, with a half-life of 10 min. Most of the injected dose is distributed to the kidney and liver and potentially corrective levels are also observed in heart, lung and spleen. Brain uptake is minimal. The enzyme is largely mannose 6-phosphorylated and takes up rapidly by PPT1-deficient immortalized lymphoblasts derived from infantile neuronal ceroid lipofuscinosis patients

Ppt1 plays a role in modulating the early stages of vesicle formation. There may be a connection between Ppt1 and bone morphogenetic protein signaling at the cellular level. Expression of wild-type Ppt1 in the adult visual system using GMR-Gal4 alters the external and internal organization of the adult retina. When co-expressed UAS-dynamin with Ppt1 there is a significant enhancement of the rough eye phenotype

defect in the palmitoyl-(protein) hydrolase gene causes a neurodegenerative disorder. Depalmitoylation of the still uncharacterized substrate(s) of the enzyme is critical for postnatal development or maintainance of cortical neurons

epileptic seizures in adult rats lead to progressive and remarkable increase in enzyme activity inlimbic areas of the brain, the enzyme may protect neurons from excitotoxicity and have a role in synaptic plasticity, enzyme deficiency causes progressive neurological disorder infantile neuronal ceroid lipofuscinosis, INCL

PPT1 deficiency causes progressive neurological disorder infantile neuronal ceroid lipofuscinosis, only in neurons of the cerebral and cerbellar cortexes and retina not in other cell types, characterized by early loss of vision and massiv neuronal death

PPT1 deficiency causes, together with tripeptidyl peptidase 1 deficiency, progressive neurological disorder infantile neuronal ceroid lipofuscinosis, a group of at least 8 inherited, progressive encephalopathies that are characterized by lipofuscin-like inclusions in various tissues and have been classified as CNL1-CNL8

altough the ppt-1 gene is not essential for the animal‘s survival, its mutation results in a mild developmental and reproductive phenotype, affects the number and size of mitochondria and results in an abnormality in mitochondrial morphology

Ppt1 modulates the activity of several pathways known to play a role in synaptic development either directly through its depalmitoylation activity or indirectly through effects on general endocytic mechanisms

the most severe form of neuronal ceroid lipofuscinoses, infantile neuronal ceroid lipofuscinosis (INCL), is caused by mutations in the CLN1 gene, resulting in a deficiency of the lysosomal enzyme, palmitoyl protein thioesterase 1

PPT1 deficiency leads to abnormally low levels of soluble synaptic vesicle proteins like synaptobrevin 2 and SNAP25, that are known to undergo palmitoylation and are critical for fusion, exocytosis, recycling, and regeneration of fresh synaptic vesicles

defect in the palmitoyl-(protein) hydrolase gene causes a neurodegenerative disorder. Depalmitoylation of the still uncharacterized substrate(s) of the enzyme is critical for postnatal development or maintainance of cortical neurons

epileptic seizures in adult rats lead to progressive and remarkable increase in enzyme activity inlimbic areas of the brain, the enzyme may protect neurons from excitotoxicity and have a role in synaptic plasticity, enzyme deficiency causes progressive neurological disorder infantile neuronal ceroid lipofuscinosis, INCL

PPT1 deficiency causes progressive neurological disorder infantile neuronal ceroid lipofuscinosis, only in neurons of the cerebral and cerbellar cortexes and retina not in other cell types, characterized by early loss of vision and massiv neuronal death

PPT1 deficiency causes, together with tripeptidyl peptidase 1 deficiency, progressive neurological disorder infantile neuronal ceroid lipofuscinosis, a group of at least 8 inherited, progressive encephalopathies that are characterized by lipofuscin-like inclusions in various tissues and have been classified as CNL1-CNL8

altough the ppt-1 gene is not essential for the animal‘s survival, its mutation results in a mild developmental and reproductive phenotype, affects the number and size of mitochondria and results in an abnormality in mitochondrial morphology

Ppt1 modulates the activity of several pathways known to play a role in synaptic development either directly through its depalmitoylation activity or indirectly through effects on general endocytic mechanisms

the most severe form of neuronal ceroid lipofuscinoses, infantile neuronal ceroid lipofuscinosis (INCL), is caused by mutations in the CLN1 gene, resulting in a deficiency of the lysosomal enzyme, palmitoyl protein thioesterase 1

PPT1 deficiency leads to abnormally low levels of soluble synaptic vesicle proteins like synaptobrevin 2 and SNAP25, that are known to undergo palmitoylation and are critical for fusion, exocytosis, recycling, and regeneration of fresh synaptic vesicles

Drosophila C-terminal Src kinase is an enhancer of the Ppt1 phenotype. Mutations in the fear of intimacy gene are also identified as enhancers. Mutations in zipper or mutations at the Drosophila IGF-II mRNA-binding protein locus enhance the degenerative phenotype. The tsg alleles tsg2 and tsg4 both enhance the rough eye phenotype produced by Ppt1 expression

three potential asparagine-linked glycosylation sites are found near the carboxyl terminus of the protein at positions 199, 214, and 234. Glycosylation of the amino acid 234 demonstrated experimentally

N-glycosylation of N197 and N232, but not N212, is essential for enzyme activity and intracellular transport. Deglycosylation of overexpressed PPT1 produced in neurons and fibroblasts demonstrates differentially modified PPT1 in different cell types

enzyme contains 2 putative cleavage sites for the kex-related endopeptidase Krp1p, the precursor is proteolytically processed to form distinct Ppt1p and Dolpp1p domains, Arg354 is crucial for the processing

overexpression of PPT2 in an insect-baculovirus expression system, secretion of the recombinant enzyme to the culture medium, expression of mutant PPT2 in COS cells, subcloning in Escherichia coli XL1-blue

DNA sequence determination and analysis, enzyme is encoded in frame with a second gene coding for an indispensable dolichol pyrophosphatase, gene pdf1, strains bearing a deletion of the entire pdf1 open reading frame are nonviable, due to Dolpp1p deficiency, and are rescued by pdf1 expression plasmid, mutations only in the palmitoyl protein thioesterase 1 domain results in cells abnormally sensitive to sodium vanadate and elevated extracellular pH, the pdf1-deficient phenotype is complemented by the human PPT1 gene

loss-of-function allele, although endocytosis and endo-lysosomal trafficking does occur in Ppt1 mutant garland cells, there is a reduced level of uptake and a decreased rate of trafficking to the lysosomes

loss-of-function allele, although endocytosis and endo-lysosomal trafficking does occur in Ppt1 mutant garland cells, there is a reduced level of uptake and a decreased rate of trafficking to the lysosomes

naturally occurring mutation, recombinant enzyme shows 32.8% of the wild-type activity, mutation is associated with the juvenile form of neuronal ceroid lipofuscinosis, no binding of mannose 6-phosphate receptor

naturally occurring mutation, recombinant enzyme is nearly inactive showing an activity below 2% of the wild-type activity, mutation is associated with the infantile form of neuronal ceroid lipofuscinosis, no binding of mannose 6-phosphate receptor

naturally occurring mutation, recombinant enzyme shows 5.9% of the wild-type activity, mutation is associated with the juvenile form of neuronal ceroid lipofuscinosis, no binding of mannose 6-phosphate receptor

naturally occurring mutation, recombinant enzyme is nearly inactive showing an activity below 2% of the wild-type activity, mutation is associated with the infantile form of neuronal ceroid lipofuscinosis, no binding of mannose 6-phosphate receptor

naturally occurring mutation, recombinant enzyme is nearly inactive showing an activity below 2% of the wild-type activity, mutation is associated with the infantile form of neuronal ceroid lipofuscinosis, no binding of mannose 6-phosphate receptor

naturally occurring mutation, recombinant enzyme shows 7.3% of the wild-type activity, mutation is associated with the late infantile form of neuronal ceroid lipofuscinosis, no binding of mannose 6-phosphate receptor

naturally occurring mutation, recombinant enzyme is nearly inactive showing an activity below 2% of the wild-type activity, mutation is associated with the infantile form of neuronal ceroid lipofuscinosis, no binding of mannose 6-phosphate receptor, accumulation of the recombinant mutant enzyme in the endoplamic reticulum due to decreased degradation turnover

naturally occurring mutation, recombinant enzyme shows 6.8% of the wild-type activity, mutation is associated with the juvenile form of neuronal ceroid lipofuscinosis, no binding of mannose 6-phosphate receptor

naturally occurring mutation, mutation is associated with the late onset form of infantile neuronal ceroid lipofuscinosis, the mutant enzymes shows minor altered intracellular localization in transfected cells and are localized in the presynaptic space and neuronal shaft, about 10fold reduced activity

naturally occurring mutation, recombinant enzyme is nearly inactive showing an activity below 2% of the wild-type activity, mutation is associated with the infantile form of neuronal ceroid lipofuscinosis, no binding of mannose 6-phosphate receptor

naturally occurring mutation, recombinant enzyme is nearly inactive showing an activity below 2% of the wild-type activity, mutation is associated with an unclassified form of neuronal ceroid lipofuscinosis

naturally occurring mutation, recombinant enzyme is nearly inactive showing an activity below 2% of the wild-type activity, mutation is associated with an unclassified form of neuronal ceroid lipofuscinosis

naturally occurring mutation, mutation is associated with the late onset form of infantile neuronal ceroid lipofuscinosis, the mutant enzymes shows minor altered intracellular localization in transfected cells and are localized in the presynaptic space and neuronal shaft, about 10fold reduced activity

naturally occurring mutations delPhe84 and insCys45, mutation is associated with the late onset form of infantile neuronal ceroid lipofuscinosis, the mutant enzymes shows severely altered intracellular localization in transfected cells and are targeted to the endoplasmic reticulum, about 10fold reduced activity

if patients are diagnosed with any type of mental and/or physical retardation accompanied by strong and severe visual impairment, then the case physician may consider the possibility of infantile neuronal ceroid lipofuscinosis and conduct an examination of PPT activity level